Ohio Content Standard; Eighth Grade; Measurement
8. Find the sum of interior and exterior angles of regular convex polygons with and without measuring the angles with a protractor.
Students will use the Angle Sum Applet to explore the interior angle sums of different polygons. After the instructor demonstrates, students will use triangualtion, or creating triangles inside a polygon by connecting vertices, to determine the angle sums. Students will compare each polygon's number of sides, number of interior triangles and angle sums to find patterns. Students should eventually discover that for any convex polygon, the interior angle sum may be found by 180(the number of sides - 2).
Supporting Resource
A study found that virtual manipulatives provide opportunities for more flexible thinking and problem-solving than pencil-and-paper activities or physical manipulatives. This research concluded that virtual manipulatives were invaluable to learning geometric concepts. These activities also engage the learner while encouraging discussion and questioning. References:
Wu-Yuin, H., Jia-Han, S., Yueh-Min, H., & Jian-Jie, D. (2009). A Study of Multi-Representation of Geometry Problem Solving with Virtual Manipulatives and Whiteboard System. Journal of Educational Technology & Society, 12(3), 229-247.
Tried and True/
New and Innovative
This is a new and innovative method of technology because virtual manipulatives are not used regularly in the classroom setting, though there are many applets available, especially for mathematics. Students probably have not used online models to analyze mathematical concepts in the past.
Content Area
Curriculum Standard
8. Find the sum of interior and exterior angles of regular convex polygons with and without measuring the angles with a protractor.
Technology
Description
Supporting Resource
References:
Wu-Yuin, H., Jia-Han, S., Yueh-Min, H., & Jian-Jie, D. (2009). A Study of Multi-Representation of Geometry Problem Solving with Virtual Manipulatives and Whiteboard System. Journal of Educational Technology & Society, 12(3), 229-247.
Tried and True/
New and Innovative